Process for producing FePt-based sputtering target

Patent metadata

Field	Value
Publication number	US-9314845-B2
Application number	US-201414328106-A
Country	US
Kind code	B2
Filing date	Jul 10, 2014
Priority date	Jan 13, 2012
Publication date	Apr 19, 2016
Grant date	Apr 19, 2016

Abstract

A process for producing an FePt-based sputtering target includes adding C powder containing unavoidable impurities and metal oxide powder containing unavoidable impurities to FePt-based alloy powder containing Pt in an amount of 40 at % or more and 60 at % or less with the balance being Fe and unavoidable impurities so that the C powder and the metal oxide powder are contained to satisfy:

0<α≦20;

10≦β<40; and

20≦α+β≦40,
where α and β represent contents of the C powder and the metal oxide powder by vol %, respectively, based on a total amount of the FePt-based alloy powder, the C powder, and the metal oxide powder, followed by mixing the FePt-based alloy powder, the C powder, and the metal oxide powder to produce a powder mixture.

First claim

The invention claimed is:

1. A process for producing an FePt-based sputtering target, comprising:
adding C powder containing unavoidable impurities and metal oxide powder containing unavoidable impurities to FePt-based alloy powder containing Pt in an amount of 40 at % or more and 60 at % or less with the balance being Fe and unavoidable impurities so that the C powder and the metal oxide powder are contained to satisfy:
0<α≦20;

10≦β<40; and

20≦α+β≦40,

where α and β represent contents of the C powder and the metal oxide powder by vol %, respectively, based on a total amount of the FePt-based alloy powder, the C powder, and the metal oxide powder, followed by mixing the FePt-based alloy powder, the C powder, and the metal oxide powder to produce a powder mixture; and
molding the produced powder mixture while the powder mixture is heated under pressure.

2. The process for producing an FePt-based sputtering target according to claim 1 ,
wherein a phase consisting of the C phase and the metal oxide phase in the obtained FePt-based sputtering target has an average size of 0.4 μm or less as determined by an intercept method.

3. The process for producing an FePt-based sputtering target according to claim 2 ,
wherein the mixing to produce the powder mixture is performed in an atmosphere in the presence of oxygen.

4. The process for producing an FePt-based sputtering target according to claim 3 ,
wherein oxygen is supplied to the atmosphere from outside of the atmosphere.

5. The process for producing an FePt-based sputtering target according to claim 4 ,
wherein the oxygen is supplied by supplying air.

6. The process for producing an FePt-based sputtering target according to claim 3 ,
wherein the atmosphere is composed substantially of an inert gas and oxygen.

7. The process for producing an FePt-based sputtering target according to claim 3 ,
wherein a concentration of oxygen in the atmosphere is 10 vol % or higher and 30 vol % or lower.

8. The process for producing an FePt-based sputtering target according to claim 3 ,
wherein the atmosphere is released to air during the mixing.

9. The process for producing an FePt-based sputtering target according to claim 1 ,
wherein the metal oxide contains at least one of SiO 2 , TiO 2 , Ti 2 O 3 , Ta 2 O 5 , Cr 2 O 3 , COO, CO 3 O 4 , B 2 O 3 , Fe 2 O 3 , CuO, Cu 2 O, Y 2 O 3 , MgO, Al 2 O 3 , ZrO 2 , Nb 2 O 5 , MoO 3 , CeO 2 , Sm 2 O 3 , Gd 2 O 3 , WO 2 , WO 3 , HfO 2 , and NiO 2 .

10. The process for producing an FePt-based sputtering target according to claim 1 ,
wherein the mixing to produce the powder mixture is performed in an atmosphere in the presence of oxygen.

11. The process for producing an FePt-based sputtering target according to claim 10 ,
wherein oxygen is supplied to the atmosphere from outside of the atmosphere.

12. The process for producing an FePt-based sputtering target according to claim 11 ,
wherein the oxygen is supplied by supplying air.

13. The process for producing an FePt-based sputtering target according to claim 10 ,
wherein the atmosphere is air.

14. The process for producing an FePt-based sputtering target according to claim 10 ,
wherein the atmosphere is composed substantially of an inert gas and oxygen.

15. The process for producing an FePt-based sputtering target according to claim 10 ,
wherein a concentration of oxygen in the atmosphere is 10 vol % or higher and 30 vol % or lower.

16. The process for producing an FePt-based sputtering target according to claim 10 ,
wherein the atmosphere is released to air during the mixing.

17. The process for producing an FePt-based sputtering target according to claim 1 ,
wherein an atmosphere when the powder mixture is molded while heated under pressure is a vacuum or an inert gas atmosphere.

18. The process for producing an FePt-based sputtering target according to claim 1 ,
wherein the FePt-based alloy powder is produced by an atomizing method.

19. The process for producing an FePt-based sputtering target according to claim 18 ,
wherein the atomizing method is performed using argon gas or nitrogen gas.

20. The process for producing an FePt-based sputtering target according to claim 1 ,
wherein the obtained FePt-based sputtering target is used for a magnetic recording medium.

Assignees

• Tanaka Precious Metal Ind

Inventors

• Miyashita Takanobu
• Goto Yasuyuki
• Yamamoto Takamichi
• Kushibiki Ryousuke
• Aono Masahiro
• Nishiura Masahiro

Classifications

• C22C5/04 Primary

  Alloys based on a platinum group metal · CPC title

• C22C38/16

  containing copper · CPC title

• C23C14/3414

  Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy · CPC title

• C22C1/0466

  Alloys based on noble metals · CPC title

• B22F2201/03

  Oxygen · CPC title